Triple Transport Flashcards
Substances may move into and out of cells across the cell membranes via…
Diffusion
Diffusion is…
The spreading out of particles resulting in a net movement from an area of higher concentration to an area of lower concentration
Substances that diffuse
Some of the substances transported in and out of cells by diffusion are oxygen and carbon dioxide in gas exchange, and of the waste product urea from cells into the blood plasma for excretion in the kidney
Factors that affect diffusion
-Difference in concentration (concentration gradient)
-The temperature
-The surface area of the membrane
Why does a single celled organism have a high SA - V ratio?
This allows sufficient transport of molecules into and out of the cell to meet the needs of the organism.
What’s the equation for SA to V ratio
SA/vol
The effectiveness of an exchange surface is increased by having:
A large surface area
A membrane that is thin to provide a short diffusion pathway
An efficient blood supply (in animals)
Efficient ventilation (in animals for gaseous exchange)
Adaptations of
